The diverter valve in the tub isn't exactly diverting very well :) When turned to the shower setting, water continues to pour from the tub faucet as well, wasting water and leaving little pressure from the shower head.

I've tried to take apart the diverter assembly, but it seems that the aseembly just spins in the pipe and won't actually come out. Is it cross-threaded or something like that? Does the entire pipework need repair/replacing?